ERWSD conducts water quality sampling as water year 2024 comes to an end
You won’t see any fireworks on Sept. 30, but Oct. 1 marks the first day of the 2025 water year, a 12-month period that reflects both winter snow accumulation and summer rainfall in precipitation totals. It’s used to track how much precipitation falls in specific areas and predict how much surface water and groundwater will be available.
Gore Creek, Eagle River, and their aquifers are the sources for most drinking water provided between East Vail and Edwards and they both serve as the receiving waters for wastewater effluent – or cleaned water. Since these waterways do so much for us, Eagle River Water & Sanitation District monitors snowpack and streamflow data throughout the water year to gauge potential water supply conditions and guide operational strategies that ensure our limited water resources are used efficiently and effectively.
In the Eagle River Valley, it is typical for high-country snowpack to increase from October through April and then melt off by June. The melting of the snowpack in spring should sustain water flow in streams and rivers throughout the year, and it is normal to see flows increase in spring, and then slowly decrease through the summer and into fall. For example, mid-September streamflows in the Eagle River through Avon were about 85 CFS (cubic feet per second), which is about 35 times less than peak flow in June.
The district also monitors water quality in our watershed. Unlike water supply and demand, which is continually monitored and analyzed, we conduct periodic water quality sampling and one multi-day, multi-site sampling event of Gore Creek and the Eagle River. This annual event happens towards the end of the water year when streamflow is typically low and predictable, and data and samples can be collected safely.
This two-day water quality sampling event took place Sept. 3 and 4 and it was the 17th year of this technical and meticulous analysis. Data was collected across 27 sites to calculate flow rate, and more than a dozen different water quality parameters were either collected in the field or later analyzed with laboratory equipment. Field measurements included pH, temperature, conductivity, and dissolved oxygen; and water samples were sent off for laboratory analyses of nutrients (nitrogen and phosphorous), metals, and more. Data and analyses from this annual sampling event are combined with additional water quality data and macroinvertebrate data from across the watershed and evaluated in an annual study.
As we enter the new water year the district will keep a close eye on snowpack data once again. You can keep track too using the ERWSD Snow Water Equivalent Graphs beginning in early November on the district’s climate, water supply, and drought webpage.